Testing Models with SimMock

SimMock and CMocka Testing for Model Developers

The DSE ModelC Library includes a SimMock source code library which may be used to develop integration tests for Models. With the SimMock library, a Model Developer is able to easily develop CMocka Testcases which:

Validate a model configuration and confirm the Models operation.
Develop scenarios where expected signal exchange is verified.
Inject network messages into the simulation or model (e.g. CAN frames) and read network messages.
Check expected values for both scalars (Signals) and messages (Network).
Stack several Model Instances within one SimMock and confirm their interoperation.

Example Test Files

network/test_network.c

#include <dse/testing.h>
#include <dse/logger.h>
#include <dse/mocks/simmock.h>

static int test_setup(void** state)
{
    const char* inst_names[] = {
        "target_inst",
        "network_inst",
    };
    char* argv[] = {
        (char*)"test_runnable",
        (char*)"--name=target_inst;network_inst",
        (char*)"--logger=5",  // 1=debug, 5=QUIET (commit with 5!)
        (char*)"../../../../tests/cmocka/network/stack.yaml",
        (char*)"../../../../tests/cmocka/network/signalgroup.yaml",
        (char*)"../../../../tests/cmocka/network/network.yaml",
        (char*)"../../../../tests/cmocka/network/model.yaml",
        (char*)"../../../../tests/cmocka/network/runnable.yaml",
    };
    SimMock* mock = simmock_alloc(inst_names, ARRAY_SIZE(inst_names));
    simmock_configure(mock, argv, ARRAY_SIZE(argv), ARRAY_SIZE(inst_names));
    simmock_load(mock);
    simmock_setup(mock, "signal", "network");

    /* Return the mock. */
    *state = mock;
    return 0;
}

static int test_teardown(void** state)
{
    SimMock* mock = *state;
    simmock_exit(mock, false);
    simmock_free(mock);
    return 0;
}

#define SIG_reset_counters  0
#define SIG_task_init_done  1
#define SIG_task_5_active   2
#define SIG_task_10_active  3
#define SIG_task_20_active  4
#define SIG_task_40_active  5
#define SIG_task_5_counter  6
#define SIG_task_10_counter 7
#define SIG_task_20_counter 8
#define SIG_task_40_counter 9

void test_network__network2target2network(void** state)
{
    SimMock*   mock = *state;
    ModelMock* network_model = &mock->model[1];
    assert_non_null(network_model);

    /* 0-19.5ms */
    {
        for (uint32_t i = 0; i < 39; i++) {
            assert_int_equal(simmock_step(mock, true), 0);
        }
        SignalCheck s_checks[] = {
            { .index = SIG_task_init_done, .value = 1.0 },
            { .index = SIG_task_5_active, .value = 1.0 },
            { .index = SIG_task_5_counter, .value = 3.0 },
            { .index = SIG_task_10_active, .value = 1.0 },
            { .index = SIG_task_10_counter, .value = 1.0 },
            { .index = SIG_task_20_active, .value = 0.0 },
            { .index = SIG_task_20_counter, .value = 0.0 },
        };
        simmock_signal_check(
            mock, "target_inst", s_checks, ARRAY_SIZE(s_checks), NULL);
        simmock_signal_check(
            mock, "network_inst", s_checks, ARRAY_SIZE(s_checks), NULL);
    }
    /* Inject a message carrying the reset_counters signal. */
    uint8_t buffer[8] = { 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
    simmock_write_frame(mock->sv_network_tx, "can_bus", buffer, 8, 0x1f0u, 0);
    assert_int_equal(simmock_step(mock, true), 0);
    /* 20ms */
    {
        for (uint32_t i = 0; i < 1; i++) {
            assert_int_equal(simmock_step(mock, true), 0);
        }
        SignalCheck s_checks[] = {
            { .index = SIG_task_init_done, .value = 1.0 },
            { .index = SIG_task_5_active, .value = 1.0 },
            { .index = SIG_task_5_counter, .value = 1.0 },
            { .index = SIG_task_10_active, .value = 1.0 },
            { .index = SIG_task_10_counter, .value = 1.0 },
            { .index = SIG_task_20_active, .value = 1.0 },
            { .index = SIG_task_20_counter, .value = 1.0 },
        };
        FrameCheck f_checks[] = {
            { .frame_id = 0x1f4u, .offset = 1, .value = 0x02 },
            { .frame_id = 0x1f4u, .offset = 2, .value = 0x02 },
            { .frame_id = 0x1f4u, .offset = 3, .value = 0x02 },
            { .frame_id = 0x1f5u, .offset = 4, .value = 0x02 },
            { .frame_id = 0x1f7u, .offset = 4, .value = 0x02 },
        };
        simmock_print_scalar_signals(mock, LOG_DEBUG);
        simmock_print_network_frames(mock, LOG_DEBUG);
        assert_int_equal(network_model->sv_network->length[0] > 0, true);
        simmock_signal_check(
            mock, "network_inst", s_checks, ARRAY_SIZE(s_checks), NULL);
        simmock_frame_check(
            mock, "network_inst", "can_bus", f_checks, ARRAY_SIZE(f_checks));
    }
}

int run_network_tests(void)
{
    void*                   s = test_setup;
    void*                   t = test_teardown;
    const struct CMUnitTest tests[] = {
        cmocka_unit_test_setup_teardown(
            test_network__network2target2network, s, t),
    };
    return cmocka_run_group_tests_name("NETWORK", tests, NULL, NULL);
}

References and Further Reading

Testing with CMocka